1. Field of the Invention
The present invention relates to an intravaginal contraceptive device such as a diaphragm or pessary.
2. Description of the Prior Art
Contraceptive devices of this type are already known from NL-A-78.04542. The diaphragm described in this patent application comprises a cap-like body, with a circular, somewhat rigid but nevertheless elastic peripheral structure. The edge generally comprises a spring retaining the shape of the diaphragm. Both the edge and the cap-like body may be formed of the same or different elastomers. The opposing sides of the edge may be folded together to facilitate the insertion of the diaphragm into the vagina.
After being inserted in the vaginal cavity, mostly in close proximity to the cervical os, contraceptive devices of this type form a sealing barrier between the vagina and the cervical os, the spring strongly forcing the elastic edge into engagement with the inner wall of the vagina. The sealing effect of the edge prevents spermatozoids from penetrating the uterus.
One disadvantage of the known contraceptive device of the type described above is, that their outer diameter is practically invariable, thereby limiting the applicability of said devices. As a matter of fact a diaphragm or pessary with a given diameter can only be used by a restricted group of users. As a result, the manufacturers of these devices must have an extensive assortment of diaphragms or pessaries with different diameters (e.g. ranging from 55 up to 90 mm). It will be obvious, that this leads to notable investments, while the process of manufacturing will be complicated by the diversity of the manufactured products.
The European patent application No. 79102122.3 (publication No. 6609) describes a diaphragm of the type described before, wherein the peripheral structure houses one or more adjustable shape-retaining sections, commonly made out of flexable metal. A limited possibility of adjusting the outer diameter of the contraceptive device is achieved by these adjustable shape-retaining sections. By adjusting the diaphragm, a more or less fixed shape is given to the device, but there will be no optimal adaption after inserting the device into the vaginal cavity.
Another major disadvantage, as relating to the user resides in the poor ability of the known device to adapt itself to changing conditions, to which it is subjected. The environment into which the device is placed is part of a living organism and is therefore not rigid and unchangeable. Especially the inner diameter of the vaginal cavity may change under influence of physical and mental circumstances. It is not imaginary then, that the known contraceptive device looses part of its sealing capacity, thereby reducing its reliability.
The object of the contraceptive device according to the invention is to overcome said disadvantages in an easy nevertheless effective way.